The invention relates to an escalator or a moving walkway.
Escalators and moving walkways comprise tensioning chains at which step bands or pallet bands, respectively, rotate. The tensioning chains, indeed, are notedly stable and dimensioned to have sufficient safety margin, however, they are subject to wear resulting in an elongation of the chains.
Chain tensioning devices are generally known that are incorporated into the turn-around area of escalators and moving walkways in order to keep the chain in a tensioned condition also in the case of an undesired elongation thereof and that are intended to prevent the chain from coming off the chain wheels, and consequently preventing the steps or step run-in parts, respectively, from colliding with one another.
It has become known for quite a long time now, to employ safety switches that are to switch off the escalator in the case of the chain exceeding a given elongation.
An escalator of the this kind is known from German utility model DE-GM 298 09 268. With this approach, a safety switching for escalators is provided in which with the aid of a potentiometer or an optical sensor that responds to corresponding optical markers and triggers a calibrated cam switch, the monitoring of the chain tensioning device is to be achieved.
From DE 103 22 955 B4 an escalator is known that comprises a tensioning station for the step chain that is slidably mounted with respect to a frame of the escalator. The relative movement between a bearing carriage or slide and the frame is continuously detected with the aid of a position sensor. The position sensor subsequently outputs an analog output signal depending on the present position to an evaluation unit that serves to translate or convert the tension value detected into the respective elongation of the chain, that is to say the offset or displacement of the bearing carriage. The tensioning station comprises a pressure spring by means of which the step chain is kept under tension.
The escalators and moving walkways known so far, however, all exhibit the disadvantage that the tensioning station is accommodated and aligned on the support structure. Moreover, additional laterally arranged components for supporting and guiding the tensioning station are required with the approaches or solutions known so far. This leads to an increased amount of raw materials and supplies and to a time-consuming and cost-intensive installation.
The manufacturers of escalators and moving walkways, however, constantly make an effort to not only reduce the costs for installation, but also the costs of manufacture of escalators and moving walkways. Moreover, the competitive environment requires short delivery times for escalators and moving walkways and thus a production as fast as possible.
Therefore, it is the object of the invention to produce an escalator or moving walkway of the aforementioned general type that can be manufactured with a production expenditure as low as possible and cost-efficiently and that provides a simplified installation.